The present invention relates to temperature control for a refrigerated space, such as a refrigerated trailer.
It is desirable for cargo in a refrigerated trailer to be kept at or near a set point temperature. Typically, discharge air from a refrigeration system entering the refrigerated trailer is colder than the set point temperature and can cause portions of cargo near the discharge air vent to freeze. It is desirable to prevent portions of the cargo from freezing, known as top freeze, when the set point temperature is set to be above freezing while maintaining the temperature of the cargo as close as possible to the set point. Current methods are either incapable of meeting both requirements or require complex fluid control systems and combined algorithms for temperature control, which interfere or even counteract each other and which require significant control software complexity.